ML16141B024
| ML16141B024 | |
| Person / Time | |
|---|---|
| Site: | Oconee, Mcguire, Catawba, McGuire  |
| Issue date: | 06/20/1996 |
| From: | NRC (Affiliation Not Assigned) |
| To: | |
| Shared Package | |
| ML16141B025 | List: |
| References | |
| NUDOCS 9607010346 | |
| Download: ML16141B024 (12) | |
Text
UNITED STATES NUCLEAR REGULATORY COMMISSION o
WASHINGTON, D.C. 20555-0001 SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION REQUEST TO USE CODE CASE N-533 FOR DUKE POWER COMPANY CATAWBA NUCLEAR STATION, UNITS 1 AND 1.
MCGUIRE NUCLEAR STATION, UNITS I AND 2.
AND OCONEE NUCLEAR STATION, UNITS 1. 2. AND 3 DOCKET NOS. 50-413, 50-414, 50-369, 370.
50-269, 50-270, AND 50-287
1.0 INTRODUCTION
The Technical Specifications for Catawba Nuclear Station, Units 1 and 2, McGuire Nuclear Station, Units 1 and 2, and Oconee Nuclear Station, Units 1, 2, and 3 state that the inservice inspection of the American Society of Mechanical Engineers (ASME) Code Class 1, 2, and 3 components shall be performed in accordance with Section XI of the ASME Boiler and Pressure Vessel Code and applicable Addenda as required by Title 10 of the Code of Federal Regulations (10 CFR) 50.55a(g), except where specific written relief has been granted by the Commission pursuant to 10 CFR 50.55a(g)(6)(i). Section.
50.55a(a)(3) states that alternatives to the requirements of paragraph (g) may be used, when authorized by the NRC, if (i) the proposed alternatives would provide an acceptable level of quality and safety, or (ii) compliance with the specified requirements would result in hardship or unusual difficulties without a compensating increase in the level of quality and safety.
Pursuant to 10 CFR 50.55a(g)(4), ASME Code Class 1, 2, and 3 components (including supports) shall meet the requirements, except the design and access provisions and the preservice examination requirements, set forth in the ASME Code,Section XI, "Rules for Inservice Inspection of Nuclear Power Plant Components," to the extent practical within the limitations of design, geometry, and materials of construction of the components. The regulations require that inservice examination of components and system pressure tests conducted during the first 10-year interval and subsequent intervals comply with the requirements in the latest edition and addenda of Section XI of the ASME Code incorporated by reference in 10 CFR 50.55a(b) 12 months prior to the start of the 120-month interval, subject to the limitations and modifications listed therein. The applicable edition of Section XI of the ASME Code for the Catawba Nuclear Station, Units 1 and 2 first 10-year inservice inspection (ISI) interval is the 1980 Edition through Winter 1981 Addenda. The applicable edition of Section XI of the ASME Code for McGuire Nuclear Station, Units 1 and 2, and Oconee Nuclear Station, Units 1, 2, and 3 second and third 10-year inservice inspection (ISI) interval, respectively, is the 1989 Edition. The components (including supports) may meet the requirements set forth in subsequent editions and addenda of the ASME Code incorporated by reference in 10 CFR 50.55a(b) subject to the limitations and modifications listed therein and subject to Commission approval.
9607010346 960620 PDR ADOCK 05000269 p
-2 Pursuant to 10 CFR 50.55a(g)(5), if the licensee determines that conformance with an examination requirement of Section XI of the ASME Code is not practical for its facility, information shall be submitted to the Commission in support of that determination and a request made for relief from the ASME Code requirement. After evaluation of the determination, pursuant to 10 CFR 50.55a(g)(6)(i), the Commission may grant relief and may impose alternative requirements that are determined to be authorized by law, will not endanger life, property, or the common defense and security, and are otherwise in the public interest, giving due consideration to the burden upon the licensee that could result if the requirements were imposed. In a letter dated May 7, 1996, Duke Power Company submitted its first, second, and third 10-year interval inservice inspection program plan request to implement Code Case N-533 "Alternative Requirements for VT-2 Visual Examination of Class 1 Insulated Pressure-Retaining Bolted Connections,Section XI, Division 1" as an alternative to Code requirements for Catawba Nuclear Station, Units 1 and 2, McGuire Nuclear Station, Units 1 and 2, and Oconee Nuclear Station, Units 1, 2, and 3, respectively.
2.0 EVALUATION The staff, has evaluated the information provided by the licensee in support of its first, second, third 10-year interval inservice inspection program plan, request to implement Code Case N-533 "Alternative Requirements for VT-2 Visual Examination of Class 1 Insulated Pressure-Retaining Bolted Connections,Section XI, Division 1" as an alternative to the Code requirements for the licensee's three plants named above.
Code Requirement:
IWA-5242(a) states that for systems borated for the purpose of controlling reactivity, insulation shall be removed from pressure-retaining bolted connections for a direct VT-2 visual examination.
Code cases are periodically published by ASME to either clarify the intent of the Code rules or to provide alternative rules to existing Code requirements.
Use of these nonmandatory Code cases for inservice inspection is subject to general acceptance by the NRC staff and incorporation into Regulatory Guide 1.147. Pursuant to 10 CFR 50.55a, other Code cases may be used provided specific authorization is granted.
Licensee's Code Relief Request:
The licensee has requested to use Code Case N-533, "Alternative Requirements for VT-2 Visual Examination of Class 1 Insulated Pressure-Retaining Bolted Connections,Section XI, Division 1."
-3 Licensee's Basis for Requesting Relief (as stated):
It is required by the 1989 ASME Code (no addenda) Subsection XI, IWA 5242 (a) "For systems borated for the purpose of controlling reactivity, insulation shall be removed from pressure retaining bolted connections for visual examination VT-2. For other components, visual examinations VT-2 may be conducted without the removal of insulation by examining the accessible and exposed surfaces and joints of the insulation.
Essentially horizontal surfaces of insulation shall be examined at each insulation joint."
Duke believes these requirements described above create a hardship for utilities that results in duplicated work activities and compromises personnel and radiation safety. Compliance with these Code requirements would necessitate removal of insulation from all pressure retaining bolted connections for visual examination VT-2 when borated Class I systems are at elevated temperatures and pressures. To remove insulation and perform VT-2 examination at elevated temperatures and pressures makes inspection more difficult and does not provide for a compensating increase in the level of quality and safety. It is also estimated that utilizing the provisions of this Code Case would reduce personnel radiation exposure by approximately 20 mr/hr per item. Duke Power believes the same level of quality and safety can be maintained by implementing the alternative means contained in Code Case N-533.
Licensee's Proposed Alternative Examination (as stated):
Duke Power proposes to apply Code Case N-533 as an alternative to the rules for visual examination of insulated components (IWA-5242) for borated Class 1 systems. Code Case N-533 states that "It is the opinion of the Committee that, as an alternative to the requirements of IWA 5242(a) to remove insulation from Class 1 pressure-retaining bolted connections to perform a VT-2 visual examination, the following requirements shall be met.
(a) A system pressure test and VT-2 visual examination shall be preformed each refueling outage without removal of insulation.
(b) Each refueling outage the insulation shall be removed from the bolted connection, and a VT-2 visual examination shall be performed.
The connection is not required to be pressurized. Any evidence of leakage shall be evaluated in accordance with IWA-5250."
-4 Paragraph IWA-5242(a) requires the removal of all insulation from pressure retaining bolted connections in systems borated for the purpose of controlling reactivity when performing VT-2 visual examinations during system pressure tests. The licensee has proposed to use Code Case N-533, which requires (1) performing the Code-required pressure test without removing the insulation, (2) examination of Class 1 bolted connections, each refueling outage, at atmospheric or static pressure with insulation removed, and (3) requires that any evidence of leakage be evaluated in accordance with IWA-5250.
Paragraph IWA-5242(a) provides requirements to ensure that leakage or evidence of leakage at bolted connections is found. Performing a VT-2 visual examination during system pressure tests as required by Code Case N-533, with the insulation in place will likely result in the detection of any significant leakage, provided a 4-hour hold time is observed prior to the VT-2 visual examination. Furthermore, performing a VT-2 visual examination after removal of the insulation at atmospheric or static pressure during outages, as specified by Code Case N-533, will allow for examination for evidence of borated water leakage. The Code Case states that any evidence of leakage.must be evaluated in accordance with IWA-5250 of Section XI.
3.0 CONCLUSION
The staff has reviewed the licensee's submittal and concluded that by using Code Case N-533 the licensee will locate and evaluate leakage, or evidence of leakage, in a manner comparable to the requirements of the Code, and thus the licensee's proposed alternative provides an acceptable level of quality and safety. Therefore, the licensee's proposed alternative for Catawba Nuclear Station, Units 1 and 2, McGuire Nuclear Station, Units 1 and 2, and Oconee Nuclear Station, Units 1, 2, and 3, to implement Code Case N-533, is authorized pursuant to 10 CFR 50.55a(a)(3)(i), provided a 4-hour hold time at test conditions is observed prior to the VT-2 visual examination. The use of this Code Case is authorized for the duration of the respective current applicable 10-year ISI intervals for the above plants, or until the Code Case is approved for general use by reference in Regulatory Guide 1.147. After that time, the licensee may continue to use Code Case N-533 with the limitations, if any, listed in Regulatory Guide 1.147.
Principal Contributor: Thomas K. McLellan Date: June 20, 1996
Nuclear Generation Duke Power Company a
June 2 1996 P. 0. Box 1006 W
Charlotte, NC 28201
SUBJECT:
CATAWBA NUCLEAR STATION, UNITS 1 AND 2, MCGUIRE NUCLEAR STATION, UNITS 1 AND 2, AND OCONEE NUCLEAR STATION, UNITS 1, 2, AND 3 AUTHORIZATION TO IMPLEMENT ASME CODE CASE N-533 (TAC NOS.
M95364, M95365, M95357, M95358, M95361, M95362, and M95363)
Dear Mr. Tuckman:
By letter dated May 7, 1996, Duke Power Company requested approval to use the provisions of ASME Code Case N-533 "Alternative Requirements for VT-2 Visual Examination of Class 1 Insulated Pressure-Retaining Bolted Connections,Section XI, Division 1," as an alternative to the Code requirements for Catawba Nuclear Station, Units 1 and 2, McGuire Nuclear Station, Units 1 and 2, and Oconee Nuclear Station, Units 1, 2, and 3. Our evaluation and conclusions of this proposed alternative are contained in the enclosed Safety Evaluation.
Approval is granted to Duke Power Company to use Code Case N-533 at the three plants named above. Details are delineated in the enclosed Safety Evaluation.
The staff has concluded that granting this approval would not result in unacceptable consequences or impair the ability to shut the plant down during normal operation or accident conditions. The staff has'determined that Duke Power Company's proposed alternative provides an acceptable level of quality and safety. Therefore, the use of the proposed alternative is authorized pursuant to 10 CFR 50.55a(a)(3)(i).
Sincerely, Original signed by Herbert N. Berkow, Director Project Directorate 11-2.
Division of Reactor Projects -
I/II Office of Nuclear Reactor Regulation Docket Nos. 50-413, 50-414, 50-369, 50-370, 50-269, 50-270, and 50-287
Enclosure:
Safety Evaluation cc w/encl: See next page DISTRIBUTION Docket File WRussell/FMiraglia SVarga PUBLIC RZimmerman OGC PDII-2 Reading JZwolinski ACRS GHill (4)
GTracy TMcLellan RCrlenjak, RII EMerschoff, RH DOCUMENT NAME:
G:\\CATAWBA\\CAT95364.RR To receive a copy of this document, indicate in the box: "C" = Copy without attachment/enclosure "E" =
Copy with attachment/enclosure "N'"
= No copy OFFICE LA:PD22:DRPE E PM:PD22:D PM:PD22:DRPE PM:PD22:DRPE OGC D: 2 NAME L.Berry*
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&erkJF' DATE 6 / 4
/96 6
/ 5 /06 6 / 5 /96 6/5 /96 6/17/96
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/96 OFFICIAL RECORD COPY
- See previous concurrence.
SEUNITED STATES 4CLEAR REGULATORY COMMIESON WASHINGTON, D.C. 20555-4001 l**
June 20, 1996 Mr. M. S. Tuckman Senior Vice President Nuclear Generation Duke Power Company P. 0. Box 1006 Charlotte, NC 28201
SUBJECT:
CATAWBA NUCLEAR STATION, UNITS 1 AND 2, MCGUIRE NUCLEAR STATION, UNITS 1 AND 2, AND OCONEE NUCLEAR STATION, UNITS 1, 2, AND 3 AUTHORIZATION TO IMPLEMENT ASME CODE CASE N-533 (TAC NOS.
M95364, M95365, M95357, M95358, M95361, M95362, and M95363)
Dear Mr. Tuckman:
By letter dated May 7, 1996, Duke Power Company requested approval to use the provisions of ASME Code Case N-533 "Alternative Requirements for VT-2 Visual Examination of Class 1 Insulated Pressure-Retaining Bolted Connections,Section XI, Division 1," as an alternative to the Code requirements for Catawba Nuclear Station, Units 1 and 2, McGuire Nuclear Station, Units 1 and 2, and Oconee Nuclear Station, Units 1, 2, and 3. Our evaluation and conclusions of this proposed alternative are contained in the enclosed Safety Evaluation.
Approval is granted to Duke Power Company to use Code Case N-533 at the three plants named above. Details are delineated in the enclosed Safety Evaluation.
The staff has concluded that granting this approval would not result in unacceptable consequences or impair the ability to shut the plant down during normal operation or accident conditions. The staff has determined that Duke Power Company's proposed alternative provides an acceptable level of quality and safety. Therefore, the use of the proposed alternative is authorized pursuant to 10 CFR 50.55a(a)(3)(i).
Sincerely, rbert N. Berkow, Director Project Directorate 11-2 Division of Reactor Projects -
I/II Office of Nuclear Reactor Regulation Docket Nos. 50-413, 50-414, 50-369, 50-370, 50-269, 50-270, and 50-287
Enclosure:
Safety Evaluation cc w/encl: See next page Mr. M. S. Tuckman Senior Vice President
Duke Power Company Catawba Nuclear Station McGuire Nuclear Station Oconee Nuclear Station cc:
Mr. M. S. Kitlan Regulatory Compliance Manager North Carolina Electric Membership Duke Power Company Corporation 4800 Concord Road P. 0. Box 27306 York, South Carolina 29745 Raleigh, North Carolina 27611 Mr. Paul R. Newton Saluda River Electric Cooperative, Legal Department (PB05E)
Inc.
Duke Power Company P. 0. Box 929 422 South Church Street Laurens, South Carolina 29360 Charlotte, North Carolina 28242 Senior Resident Inspector J. Michael McGarry, III, Esquire 4830 Concord Road Winston and Strawn York, South Carolina 29745 1400 L Street, NW.
Washington, DC 20005 Regional Administrator, Region II U.S. Nuclear Regulatory Commission North Carolina Municipal Power 101 Marietta Street, NW Suite 2900 Agency Number 1 Atlanta, Georgia 30323 1427 Meadowwood Boulevard P. 0. Box 29513 Max Batavia, Chief Raleigh, North Carolina 27626 Bureau of Radiological Health South Carolina Department of Health Mr. Peter R. Harden, IV and Environmental Control Account Sales Manager 2600 Bull Street Westinghouse Electric Corporation Columbia, South Carolina 29201 Power Systems Field Sales P. 0. Box 7288 Ms. Karen E. Long Charlotte, North Carolina 28241 Assistant Attorney General North Carolina Department of Justice County Manager of York County P. 0. Box 629 York County Courthouse Raleigh, North Carolina 27602 York, South Carolina 29745 Mr. G. A. Copp Richard P. Wilson, Esquire Licensing -
EC050 Assistant Attorney General Duke Power Company S.C. Attorney General's Office 526 South Church Street P. 0. Box 11549 Charlotte, North Carolina 28242-0001 Columbia, South Carolina 29211 Piedmont Municipal Power Agency 121 Village Drive Greer, South Carolina 29651
Duke Power Company Catawba Nu ear Station McGuire N ar Station Oconee Nuclear Station cc:
Dr. John M. Barry Mr. Ed Burchfield Mecklenburg County Compliance Department of Environmental Duke Power Company Protection Oconee Nuclear Site 700 N Tryon Street P. 0. Box 1439 Charlotte, North Carolina 29202 Seneca, South Carolina 29679 County Manager of Mecklenburg County Mr. Robert B. Borsum 720 East Fourth Street Babcock & Wilcox Charlotte, North Carolina 28202 Nuclear Power Division Suite 525 Mr. J. E. Snyder 1700 Rockville Pike Regulatory Compliance Manager Rockville, Maryland 20852 Duke Power Company McGuire Nuclear Site Manager, LIS 12700 Hagers Ferry Road NUS Corporation Huntersville, North Carolina 28078 2650 McCormick Drive, 3rd Floor Clearwater, Florida 34619-1035 Senior Resident Inspector c/o U.S. Nuclear Regulatory Senior Resident Inspector Commission U.S. Nuclear Regulatory Commission 12700 Hagers Ferry Road Route 2, Box 610 Huntersville, North Carolina 28078 Seneca, South Carolina 29678 Mr. Dayne H. Brown, Director Mr. W. R. McCollum Department of Environmental Site Vice President Health and Natural Resources Catawba Nuclear Station Division of Radiation Protection Duke Power Company P. 0. Box 27687 4800 Concord Road Raleigh, North Carolina 27611 York, South Carolina 29745 County Supervisor of Oconee County Mr. T. C. McMeekin Walhalla, South Carolina 27621 Vice President, McGuire Site Duke Power Company Mr. J. W. Hampton 12700 Hagers Ferry Road Vice President, Oconee Site Huntersville, North Carolina 28078 Duke Power Company P. 0. Box 1439 Elaine Wathen, Lead REP Planner Seneca, South Carolina 29679 Division of Emergency Management 116 West Jones Street Mr. T. Richard Puryear Raleigh, North Carolina 27603-1335 Owners Group (NCEMC)
Duke Power Company 4800 Concord Road York, South Carolina 29745
t8 REG(
UNITED STATES 8
INUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION REQUEST TO USE CODE CASE N-533 FOR DUKE POWER COMPANY CATAWBA NUCLEAR STATION, UNITS 1 AND 1.
MCGUIRE NUCLEAR STATION. UNITS 1 AND 2, AND OCONEE NUCLEAR STATION, UNITS 1. 2. AND 3 DOCKET NOS. 50-413, 50-414, 50-369, 370, 50-269, 50-270, AND 50-287
1.0 INTRODUCTION
The Technical Specifications for Catawba Nuclear Station, Units 1 and 2, McGuire Nuclear Station, Units 1 and 2, and Oconee Nuclear Station, Units 1, 2, and 3 state that the inservice inspection of the American Society of Mechanical Engineers (ASME) Code Class 1, 2, and 3 components shall be performed in accordance with Section XI of the ASME Boiler and Pressure Vessel Code and applicable Addenda as required by Title 10 of the Code of Federal Regulations (10 CFR) 50.55a(g), except where specific written relief has been granted by the Commission pursuant to 10 CFR 50.55a(g)(6)(i). Section 50.55a(a)(3) states that alternatives to the requirements of paragraph (g) may be used, when authorized by the NRC, if (i) the proposed alternatives would provide an acceptable level of quality and safety, or (ii) compliance with the specified requirements would result in hardship or unusual difficulties without a compensating increase in the level of quality and safety.
Pursuant to 10 CFR 50.55a(g)(4), ASME Code Class 1, 2, and 3 components (including supports) shall meet the requirements, except the design and access provisions and the preservice examination requirements, set forth in the ASME Code,Section XI, "Rules for Inservice Inspection of Nuclear Power Plant Components," to the extent practical within the limitations of design, geometry, and materials of construction of the components. The regulations require that inservice examination of components and system pressure tests conducted during the first 10-year interval and subsequent intervals comply with the requirements in the latest edition and addenda of Section XI of the ASME Code incorporated by reference in 10 CFR 50.55a(b) 12 months prior to the start of the 120-month interval, subject to the limitations and modifications listed therein. The applicable edition of Section XI of the ASME Code for the Catawba Nuclear Station, Units 1 and 2 first 10-year inservice inspection (ISI) interval is the 1980 Edition through Winter 1981 Addenda. The applicable edition of Section XI of the ASME Code for McGuire Nuclear Station, Units 1 and 2, and Oconee Nuclear Station, Units 1, 2, and 3 second and third 10-year inservice inspection (ISI) interval, respectively, is the 1989 Edition. The components (including supports) may meet the requirements set forth in subsequent editions and addenda of the ASME Code incorporated by reference in 10 CFR 50.55a(b) subject to the limitations and modifications listed therein and subject to Commission approval.
-2 Pursuant to 10 CFR 50.55a(g)(5), if the licensee determines that conformance with an examination requirement of Section XI of the ASME Code is not practical for its facility, information shall be submitted to the Commission in support of that determination and a request made for relief from the ASME Code requirement. After evaluation of the determination, pursuant to 10 CFR 50.55a(g)(6)(i), the Commission may grant relief and may impose alternative requirements that are determined to be authorized by law, will not endanger life, property, or the common defense and security, and are otherwise in the public interest, giving due consideration to the burden upon the licensee that could result if the requirements were imposed. In a letter dated May 7, 1996, Duke Power Company submitted its first, second, and third 10-year interval inservice inspection program plan request to implement Code Case N-533 "Alternative Requirements for VT-2 Visual Examination of Class 1 Insulated Pressure-Retaining Bolted Connections,Section XI, Division 1" as an alternative to Code requirements for Catawba Nuclear Station, Units 1 and 2, McGuire Nuclear Station, Units 1 and 2, and Oconee Nuclear Station, Units 1, 2, and 3, respectively.
2.0 EVALUATION The staff, has evaluated the information provided by the licensee in support of its first, second, third 10-year interval inservice inspection program plan, request to implement Code Case N-533 "Alternative Requirements for VT-2 Visual Examination of Class 1 Insulated Pressure-Retaining Bolted Connections,Section XI, Division 1" as an alternative to the Code requirements for the licensee's three plants named above.
Code Requirement:
IWA-5242(a) states that for systems borated for the purpose of controlling reactivity, insulation shall be removed from pressure-retaining bolted connections for a direct VT-2 visual examination.
Code cases are periodically published by ASME to either clarify the intent of the Code rules or to provide alternative rules to existing Code requirements.
Use of these nonmandatory Code cases for inservice inspection is subject to general acceptance by the NRC staff and incorporation into Regulatory Guide 1.147.
Pursuant to 10 CFR 50.55a, other Code cases may be used provided specific authorization is granted.
Licensee's Code Relief Request:
The licensee has requested to use Code Case N-533, "Alternative Requirements for VT-2 Visual Examination of Class 1 Insulated Pressure-Retaining Bolted Connections,Section XI, Division 1."
-3 Licensee's Basis for Requesting Relief (as stated):
It is required by the 1989 ASME Code (no addenda) Subsection XI, IWA 5242 (a) "For systems borated for the purpose of controlling reactivity, insulation shall be removed from pressure retaining bolted connections for visual examination VT-2. For other components, visual examinations VT-2 may be conducted without the removal of insulation by examining the accessible and exposed surfaces and joints of the insulation.
Essentially horizontal surfaces of insulation shall be examined at each insulation joint."
Duke believes these requirements described above create a hardship for utilities that results in duplicated work activities and compromises personnel and radiation safety. Compliance with these Code requirements would necessitate removal of insulation from all pressure retaining bolted connections for visual examination VT-2 when borated Class I systems are at elevated temperatures and pressures. To remove insulation and perform VT-2 examination at elevated temperatures and pressures makes inspection more difficult and does not provide for a compensating increase in the level of quality and safety. It is also estimated that utilizing the provisions of this Code Case would reduce personnel radiation exposure by approximately 20 mr/hr per item. Duke Power believes the same level of quality and safety can be maintained by implementing the alternative means contained in Code Case N-533.
Licensee's Proposed Alternative Examination (as stated):
Duke Power proposes to apply Code Case N-533 as an alternative to the rules for visual examination of insulated components (IWA-5242) for borated Class 1 systems. Code Case N-533 states that "It is the opinion of the Committee that, as an alternative to the requirements of IWA 5242(a) to remove insulation from Class 1 pressure-retaining bolted connections to perform a VT-2 visual examination, the following requirements shall be met.
(a) A system pressure test and VT-2 visual examination shall be
.preformed each refueling outage without removal of insulation.
(b) Each refueling outage the insulation shall be removed from the bolted connection, and a VT-2 visual examination shall be performed.
The connection is not required to be pressurized. Any evidence of leakage shall be evaluated in accordance with IWA-5250."
S 0
-4 Paragraph IWA-5242(a) requires the removal of all insulation from pressure retaining bolted connections in systems borated for the purpose of controlling reactivity when performing VT-2 visual examinations during system pressure tests. The licensee has proposed to use Code Case N-533, which requires (1) performing the Code-required pressure test without removing the insulation, (2) examination of Class 1 bolted connections, each refueling outage, at atmospheric or static pressure with insulation removed, and (3) requires that any evidence of leakage be evaluated in accordance with IWA-5250.
Paragraph IWA-5242(a) provides requirements to ensure that leakage or evidence of leakage at bolted connections is found. Performing a VT-2 visual examination during system pressure tests as required by Code Case N-533, with the insulation in place will likely result in the detection of any significant leakage, provided a 4-hour hold time is observed prior to the VT-2 visual examination. Furthermore, performing a VT-2 visual examination after removal of the insulation at atmospheric or static pressure during outages, as specified by Code Case N-533, will allow for examination for evidence of borated water leakage. The Code Case states that any evidence of leakage must be evaluated in accordance with IWA-5250 of Section XI.
3.0 CONCLUSION
The staff has reviewed the licensee's submittal and concluded that by using Code Case N-533 the licensee will locate and evaluate leakage, or evidence of leakage, in a manner comparable to the requirements of the Code, and thus the licensee's proposed alternative provides an acceptable level of quality and safety. Therefore, the licensee's proposed alternative for Catawba Nuclear Station, Units 1 and 2, McGuire Nuclear Station, Units 1 and 2, and Oconee Nuclear Station, Units 1, 2, and 3, to implement Code Case N-533, is authorized pursuant to 10 CFR 50.55a(a)(3)(i), provided a 4-hour hold time at test conditions is observed prior to the VT-2 visual examination. The use of this Code Case is authorized for the duration of the respective current applicable 10-year ISI intervals for the above plants, or until the Code Case is approved for general use by reference in Regulatory Guide 1.147. After that time, the licensee may continue to use Code Case N-533 with the limitations, if any, listed in Regulatory Guide 1.147.
Principal Contributor: Thomas K. McLellan Date:
June 20, 1996